debian-cis/bin/hardening/6.2.8_check_user_dir_perm.sh

#!/bin/bash

# run-shellcheck
#
# CIS Debian Hardening
#

#
# 6.2.8 Check Permissions on User Home Directories (Scored)
#

set -e # One error, it's over
set -u # One variable unset, it's over

# shellcheck disable=2034
HARDENING_LEVEL=2
# shellcheck disable=2034
DESCRIPTION="Check permissions on user home directories."

ERRORS=0

# This function will be called if the script status is on enabled / audit mode
audit() {
    for dir in $(get_db passwd | grep -Ev '(root|halt|sync|shutdown)' | awk -F: '($7 != "/usr/sbin/nologin" && $7 != "/sbin/nologin" && $7 != "/bin/false" && $7 !="/nonexistent" ) { print $6 }'); do
        debug "Working on $dir"
        debug "Exceptions : $EXCEPTIONS"
        debug "echo \"$EXCEPTIONS\" | grep -q $dir"
        if echo "$EXCEPTIONS" | grep -q "$dir"; then
            debug "$dir is confirmed as an exception"
            RESULT=$(sed "s!$dir!!" <<<"$RESULT")
        else
            debug "$dir not found in exceptions"
        fi
        if [ -d "$dir" ]; then
            dirperm=$(/bin/ls -ld "$dir" | cut -f1 -d" ")
            if [ "$(echo "$dirperm" | cut -c6)" != "-" ]; then
                crit "Group Write permission set on directory $dir"
                ERRORS=$((ERRORS + 1))
            fi
            if [ "$(echo "$dirperm" | cut -c8)" != "-" ]; then
                crit "Other Read permission set on directory $dir"
                ERRORS=$((ERRORS + 1))
            fi
            if [ "$(echo "$dirperm" | cut -c9)" != "-" ]; then
                crit "Other Write permission set on directory $dir"
                ERRORS=$((ERRORS + 1))
            fi
            if [ "$(echo "$dirperm" | cut -c10)" != "-" ]; then
                crit "Other Execute permission set on directory $dir"
                ERRORS=$((ERRORS + 1))
            fi
        fi
    done

    if [ "$ERRORS" = 0 ]; then
        ok "No incorrect permissions on home directories"
    fi

}

# This function will be called if the script status is on enabled mode
apply() {
    for dir in $(get_db passwd | grep -Ev '(root|halt|sync|shutdown)' | awk -F: '($7 != "/usr/sbin/nologin" && $7 != "/sbin/nologin" && $7 != "/bin/false" && $7 !="/nonexistent" ) { print $6 }'); do
        debug "Working on $dir"
        debug "Exceptions : $EXCEPTIONS"
        debug "echo \"$EXCEPTIONS\" | grep -q $dir"
        if echo "$EXCEPTIONS" | grep -q "$dir"; then
            debug "$dir is confirmed as an exception"
            RESULT=$(sed "s!$dir!!" <<<"$RESULT")
        else
            debug "$dir not found in exceptions"
        fi
        if [ -d "$dir" ]; then
            dirperm=$(/bin/ls -ld "$dir" | cut -f1 -d" ")
            if [ "$(echo "$dirperm" | cut -c6)" != "-" ]; then
                warn "Group Write permission set on directory $dir"
                chmod g-w "$dir"
            fi
            if [ "$(echo "$dirperm" | cut -c8)" != "-" ]; then
                warn "Other Read permission set on directory $dir"
                chmod o-r "$dir"
            fi
            if [ "$(echo "$dirperm" | cut -c9)" != "-" ]; then
                warn "Other Write permission set on directory $dir"
                chmod o-w "$dir"
            fi
            if [ "$(echo "$dirperm" | cut -c10)" != "-" ]; then
                warn "Other Execute permission set on directory $dir"
                chmod o-x "$dir"
            fi
        fi
    done
}

# This function will create the config file for this check with default values
create_config() {
    cat <<EOF
status=audit
# Put here user home directories exceptions, separated by spaces
EXCEPTIONS=""
EOF
}

# This function will check config parameters required
check_config() {
    if [ -z "$EXCEPTIONS" ]; then
        EXCEPTIONS="@"
    fi
}

# Source Root Dir Parameter
if [ -r /etc/default/cis-hardening ]; then
    # shellcheck source=../../debian/default
    . /etc/default/cis-hardening
fi
if [ -z "$CIS_ROOT_DIR" ]; then
    echo "There is no /etc/default/cis-hardening file nor cis-hardening directory in current environment."
    echo "Cannot source CIS_ROOT_DIR variable, aborting."
    exit 128
fi

# Main function, will call the proper functions given the configuration (audit, enabled, disabled)
if [ -r "$CIS_ROOT_DIR"/lib/main.sh ]; then
    # shellcheck source=../../lib/main.sh
    . "$CIS_ROOT_DIR"/lib/main.sh
else
    echo "Cannot find main.sh, have you correctly defined your root directory? Current value is $CIS_ROOT_DIR in /etc/default/cis-hardening"
    exit 128
fi